accumulator.md

EN

• <a href="https://ar.javascript.info/"
• <a href="accumulator.html" accumulator" /accumulator" accumulatoraccumulator"

accumulator" /accumulator" /accumulator" ask/accumulator"k%2Faccumulator"%2Faccumulator"

<a href="../object-basics.html" Objects: the basics

<a href="../constructor-new.html" Constructor, operator "new"

<a href="../constructor-new.html"

Create new Accumulator

importance: 5

Create a constructor function Accumulator(startingValue).

Object that it creates should:

• Store the “current value” in the property value. The starting value is set to the argument of the constructor startingValue.
• The read() method should use prompt to read a new number and add it to value.

In other words, the value property is the sum of all user-entered values with the initial value startingValue.

Here’s the demo of the code:

let accumulator = new Accumulator(1); // initial value 1

accumulator.read(); // adds the user-entered value
accumulator.read(); // adds the user-entered value

alert(accumulator.value); // shows the sum of these values

Run the demo

Open a sandbox with tests.

solution

<a href="accumulator.html#"

function Accumulator(startingValue) {
  this.value = startingValue;

  this.read = function() {
    this.value += +prompt('How much to add?', 0);
  };

}

let accumulator = new Accumulator(1);
accumulator.read();
accumulator.read();
alert(accumulator.value);

Open the solution with tests in a sandbox.